Adjustable guide for shear knives



' July 14, 1953 F. E. MUNSCHAUE R 2,645,287

ADJUSTABLE GUIDE FOR SHEAR KNIVES I Filed Oct. s, 1948 .5 a a WWW m #0 wm Im A fl E 1 my e I 5 w u x 3 Patented July'14, 195 3 UNlTED STATES PATENT oFFi'cEp,

ADJUSTABLE, GUIDE FOR SHEAR. KNIVES Frederick E. Munschauer, Buffalo, N. Y., assignor to Niagara Machine & Tool Works, Buffalo, N. Y.

Application October 6, 1948, Serial No. 53,128

3 Claims. (Cl. 164-47) This invention relates to shears and particularly to power squaring shears of the kind com-' monly employed in metal fabrication. I

In conventional shears of this class, a work receiving bed is supported at its opposite sides by side frames or columns, and the side frames or columns have upward extensions which are formed to guide a crosshead for vertical reciprocation. The bed and the crosshead carry operating shear knives which efiect shearing strokes upon vertical reciprocation of the crosshead.

Conventional practice in machines of the fore going general design is to render, the bed horizontally adjustable relative to the side frames or columns, whereby the lower shear knife may be moved horizontally toward or away from the vertical plane of movement of theupper reciprocating shear knife to adjust the horizontal clearance therebetween. Adjustment of this clearance must be made to efiiciently shear sheets particular importance and convenience when the joint bed and side frame or column unit is fabricated into an integral whole by building up the unit with welded steel plates.

The present invention provides means which dispenses with the usual adjustable connection of the bed with the machine framework and contemplates a bed construction which is at all times rigid with respect to the machine frame and may comprise a part thereof. This is accomplished by providing an upper frame construction for the shear which includes crosshead guide means which may be adjusted to adjust the plane of reciprocation of the upper shear knife toward and away from the lower shear knife in ahorizontal direction. According to the present invention, such means are provided as to render the relative horizontal adjustment between the upper andlower shear knife simpler than has heretofore been the case.

The present invention provides, in one form, crossheadguide means which has upper pivotal support, whereby its lower knife-carrying portion may be swung toward or away from the lower shear knife, with suitable means for controlling such swinging movement within micrometric limits and for securely holding the guide means in any desired adjusted position.

In a modified form of the crossheadguide-adjusting means of the present invention, the crosshead guide means is moved bodily in a horizontal or an oblique direction in such manner that the vertical attitude of the guides and the consequent truly vertical descent of the shear knife is not disturbed despite the location of the guide means in various positions of adjustment.

Several embodiments of the present invention are set forth herein by way of example and are illustrated in the accompanying drawings. However, the principles of the presentinvention are not limited to the precise forms shown and described, nor otherwise than as defined in the appended claims. In the drawings:

Fig. 1 is a fragmentary cross-sectionalview the line l-l of Fig. 3;

Fig. 2 is a fragmentary top plan view of the crosshead guide illustrated in Fig. l;

Fig. 3 is a fragmentary horizontal cross-sectional view taken approximately on the line 3--3 of Fig. 1;

Fig. 4 is a fragmentary elevational view viewed as in Fig. l, but showing an alternative means for retaining the cross-head guides in adjusted position;

Fig. 5 is a view similar to Fig. 3, but with the adjustment holding means omitted and with a modified formof cross-head guide means illustrated;

Fig. 6 is a top plan view of an arrangement similar to that illustrated in Fig. 5 but adapted for use with a shear having a single wall side frame construction, rather than double wall column construction as in the other embodiments. ,Fig. 7 is a view similar to Fig. 1 showing an alternative form of crosshead guide, adjusting means; i

Fig. 8 is a fragmentary top plan view of the guide and adjusting means of Fig. 7.

Throughout the several figures of the drawings like characters of reference denote like parts.

'In the form of the present invention illustrated in Figs. 1, 2, and 3, and referring particularly to Fig. 1, the numeral [0 designates ashear bed or respectively. Bed l0 carries a removable lower the mapart of the crosshead assembly and has an upper shear knife 22' removably attached to its front face. The crosshead assembly also includes vertically extending end members, one of which is shown at 24 in Figs. 1 and 3, the end member being adapted to move vertically in guides .associated with the side frame members ll of the shear.

The manner in which powered shearing strokes I j are imparted to the crosshead I5 is conventional,

forms no part of the present invention, and is accordingly not illustrated. The crosshead I5 may have connection with a crank or eccentric drive shaft by means of pivoted link connections in a manner which is well-understood in this art. Figs. 1 and 3 illustrate a guide bar 25 to the front of which is attached a gib 26 which cooperates with guide bar 25 to form'a guideway for the vertically extending end member 24 of crosshead I5.

At its upper end guide bar 25 has a bearing formation 28, and a pivot pin 29 extends through bearing 28 and into the opposed walls i2 and I3 which comprise side frame member At .its lower rear portion, guide bar 25 is provided with a pair of spaced coaxial bearing formations 30 4 minate at the bottom in the bearing formations 30 and 3|. It is to be understood that the construction at the opposite side frame member of the press will be identical with that just described, excepting that it is of opposite hand.

In the modification shown in Fig. 4 the only deviation from the embodiment of Figs. 1, 2, and

3 resides in the mode of pivotally adjusting the guide bar 25 at its lower end and only this much of the construction is illustrated in Fig. 4. In

.Fig. 4 the numeral 55 designates one end of a double wall side frame or column corresponding to the wall :|3.of frame member I! in the first described embodiment.

In Fig. 4 the numeral 55 designates a link which is the counterpart of adjusting rod 33 of the preand 3| and a bearing 32 formed at one end of an adjusting rod 33 is pivotally. retained coaxially between bearings 30 and 3| by means of a pivot pin 34.

A stub shaft element 35 bears at opposite sides in the walls |2 and I3 of side frame member and is held against axial displacement with respect thereto by means of a retaining plate or washer 36 and a screw 31 which cooperate with a head formation 38 at the other end of shaft element 35.

The mid-portion of shaft 35 is flattened at its front and rear faces as is clearly shown in Fig. 3, and, an opening formed through shaft element 35 at the fiat faces receives a bushing 36 which has an enlarged head portion 40 at one.

end and a reduced portion 4| at its other. A collar 43 engages over reduced portion 4| and is held fixed relative to bushing 36 by means of a locking pin 44. Beyond the reduced portion 4| bushing 39 is provided with a nut formation-46 and bushing 39 is internally threaded to cooperate with threads formed on adjusting rod 33 as at 41 in 'Fig. 3. 7

It is believed clear from the foregoing-that rotation of nut formation 46 will produce relative movementin either desired direction between bushing 39, which is retained against axial movement by the fiat sides of stub shaft 35, and the adjusting rod 33. In this way the adjusting rod 33 is projected toward or away from shaft element 35 and the lower end of guide bar 25 is thus moved pivotally about pivot pin 29 to vary the longitudinal clearance between lower shear knife l4 and upper shear knife 22.

A set screw 49 may be threaded into stub shaft 35 to engage the periphery of the bushing 39'and' thus lock the adjusting rod 33 against disturbance of its adjusted position. As appears best from Fig. 2, the rear face of adjusting bar 25 may have reinforcing ribs 50 and 5| which extend downwardly across the back of its rear face and tervious embodiment and is pivoted between bearings 30 and 3| of guide bar 25 as at 51. The opposite end of link 56 is pivotally attached to an intermediateportion of a lever 58 as at 59.- Lever '58 is pivoted at itslower end to wall 55 as at 6|], and its upper end is provided with a laterally projecting lug or block 6|.

In Fig. .4 the numerals 62 and 63 designate lugs or projections on wall 55 which serve as stop members for the lever adjusting means. A screw 55 which is threaded into lug 6| of lever 58 has a head'portion 66 which bears against the adjacent face of lug 63 when lever 58 is in locked position,

a lock nut 68 serving to. maintain this locked position. A second screw which lies behind screw 65 in Fig. 4 is likewise threaded into block BI and has a head portion 10 which bears against the adjacent face of lug 62 in the locked condition illustrated in Fig. 4, a lock nut 1| serving to maintain such condition. a

When it is desired to move the upper shear knife toward or away from the lower shear knife in a horizontal direction, either one or the other of the screws is screwed farther into block 6|, and the other is moved out or backed ofi until the two heads 66 and 10 of the screws are again in looking engagement with lugs 63' and 62. Obviously, the lock' nuts are'loosened before this adjusting operation and retightened at its conclusion.

Fig. 5 shows a modified construction which is the same as that of Figs. 1, 2', and 3 insofar as the support and adjustment of the guide bar are concerned. The embodiment of Fig. 5'differs .Figs. 1 and 3 and indicated fragmentarily at in Fig. 5.

I The embodiment shown in Fig. 6 is the same as that shown in Fig. 5, excepting that the guide bar 82 which has a dovetail groove for receiving a guide portion 83 of a crosshead 84 is associated with a side frame 86 which comprise a single wall, rather than the double wall end members of the previous embodiments. In such case the upper bearing portion corresponding to the bearing 28 of Figs. 1 and 2 is bifurcated as at 81 and 88 tostraddle a bearing 89 formed on wall 86, the three bearings being pivotally related by means of a pivot pin 90.

In the form of the present invention shown in Figs. 7 and 8, means are provided whereby shear crosshead guide bars are mounted for bodily movement backward and forward to adjust the crosshead horizontally and thus adjust the clearance of the upper shear knife relative to the lower stationary shear knife. In Fig. 7 the numeral I designates a bed and IOI a lower stationary shear knife fixed thereto. The numeral I02 designates the inner wall of a double wall end frame member which, as appear from Fig. 8, is the right-hand end frame memberof the machine. In Fig. 8 the outer wall of such end member is designated I03.

As appears from Fig. 8, an end portion I05 of the shear crosshead is provided with a dovetail guide element I06 which is slidable in a dovetail guiding formation of a crosshead guide element I 01. Element I0! is secured to a vertically extending adjustable guide supporting block I00. The guide elements I01 and supporting blocks I08 are made separately and screwed to each other merely to permit the replacement of elements I0'I when their dovetail guide formations become unduly worn.

A rigid block IIO extends between side walls I 02 and I03 and may be welded or otherwise fixed therebetween. Block IIOis provided with upper and lower inclined guidesurfaces III and H2 and guide supporting block I08 has mating upper and lower inclined surfaces H3 and I I4.

Referring particularly to Fig. '7, a screw IIE threaded into block IIO abuts the adjacent vertical face of block I08 to limit movement of block I08 rearwardly toward block I I0. A pair of studs Ill and H8 are threaded into block I08 at their inner. end and pass freely through vertically elongated slots in block IIO. At the rear face of block IIO studs II! and H8 are provided with nuts I and I2 I, respectively, which may be drawn up to urge block I08 rearwardly and thus hold the inclined surface II I through II4 in secure seating engagement.

Assuming that screw' I I6 were backed off somewhat to permit rearward adjustment of the upper shear knife designated I23 in Fig. 7, the tightening movement of nuts I20 and I2I would move block I08 rearwardly and upwardly by sliding movement of inclined faces III and I I2 of block I02. A screw I25 passes freely through a slot I26 in an overhanging ledge formation I21 of block I08 and is threaded into block IIO. This screw is subsequently tightened to lock the blocks I08 and H0 securely to each other with the inclined faces in firm and accurately aligned seating engagement. It will be seen from the foregoing that knife I23 in this embodiment is moved forwardly and rearwardly without in any way affecting its vertical attitude or its vertical plane of reciprocation.

It will be noted that in all of the various embodiments described in the foregoing the vertical height of the crosshead and the upper sheer knife is not altered by adjustment of the crosshead guide bars. The relative vertical position of the crosshead is determined by the adjustment of its connection with the drive shaft of the machine and any vertical movement of the guides incident to horizontal adjustment merely produces movement of the guides upwardly or downwardly along the engaging surfaces of the crosshead.

What is claimed is:

1. In a machine for shearing metal sheets and the like, a pair of end frame means and a bed extending therebetween and fixed rigidly thereto,

said bed including a work table having a stationary lower shear knife fixed to the rear edge thereof, a reciprocable crosshead including an upper shear knife attached thereto adjacent the lower edge of the crosshead and vertically extending slide guide formations at opposite sides thereof, means carried by each of said end frame means having vertical guide formations cooperating with the guide formations of the crosshead for guiding the opposite ends of the crosshead in a generally vertical path of movement whereby the upper shear knife is movable past the lower shear knife to effect shearing strokes, said guide means being pivoted at their upper ends to said end frame means and having screw threaded means engaging between their lower ends and said end frame means for pivotal adjustment in a generally horizontal direction transverse to the plane of the shear knives for adjusting the clearance between the shear knives;

2. In a machine for shearing metal sheets and the like, a pair of end frame means and a bed extending therebetween and fixed rigidly thereto, sai bed including a work table having a stationary lower shear knife fixed to the rear edge thereof, a reciprocable crosshead including an upper shear knife attached thereto adjacent the lower edge of the crosshead and vertically extending slide guide formations at opposite sides thereof, means carried by each of said end frame means having vertical guide formations cooperating with the guide formations of the crosshead for guiding the opposite ends of the crosshead in a generally vertical path of movement whereby the upper shear knife is movable past the lower shear knife to effect shearing strokes, each of said guide means being pivoted at its upper end to its end frame means and having adjustable locking means acting between its lower ends and its end frame means for pivotal adjustment in a generally horizontal direction transverse of the plane of the shear knives for adjusting the clearance between the shear knives.

3. In a machine for shearing metal sheets and the like, a pair of end frame means and a bed extending therebetween and fixed rigidly thereto, said bed including a work table having a stationary lower shear knife fixed to the rear edge thereof, each of said end frame means comprising a wall portion extending above and rearwardly of said work table, said wall portions being spaced in the direction of shearing, a reciprocable crosshead including an upper shear knife, slideway means for guiding the opposite, end portions of said crosshead in a generally vertical path of movement to effect shearing strokes,

means pivotally connecting said slideway means to the forward ends of said wall portions at the upper ends of said slideway means, and means on said end frame means for selectively pivotally adjusting the slideway means in a direction transverse to the plane of the knives for adjusting the clearance between the knives.

FREDERICK E. MUNSCHAUER.

References Cited in the file of this patent UNITED STATES PATENTS 

